CVE-2016-6515

Publication date 7 August 2016

Last updated 25 August 2025

Ubuntu priority

Cvss 3 Severity Score

Description

The auth_password function in auth-passwd.c in sshd in OpenSSH before 7.3 does not limit password lengths for password authentication, which allows remote attackers to cause a denial of service (crypt CPU consumption) via a long string.

Status

Show unmaintained releases

Package	Ubuntu Release	Status
openssh	17.04 zesty	Not affected
	16.10 yakkety	Not affected
	16.04 LTS xenial	Fixed 1:7.2p2-4ubuntu2.1
	14.04 LTS trusty	Fixed 1:6.6p1-2ubuntu2.8
	12.04 LTS precise	Fixed 1:5.9p1-5ubuntu1.10

Patch details

For informational purposes only. We recommend not to cherry-pick updates. How can I get the fixes?

Package	Patch details
openssh	Upstream: fcd135c

Severity score breakdown

Parameter	Value
Base score	7.5 · High
Attack vector	Network
Attack complexity	Low
Privileges required	None
User interaction	None
Scope	Unchanged
Confidentiality	None
Integrity impact	None
Availability impact	High
Vector	CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

References

Related Ubuntu Security Notices (USN)

USN-3061-1
OpenSSH vulnerabilities
15 August 2016